/// <summary>
/// Create a grid and place the points to the appropriate grid cells
/// </summary>
/// <param name="points">Point list</param>
/// <param name="iconSize">Icon size</param>
/// <param name="zoomLevel">Zoom level</param>
/// <param name="ne_lng">North east longitude of the box</param>
/// <param name="ne_lat">North east latitude of the box</param>
/// <param name="sw_lng">South west longitude of the box</param>
/// <param name="sw_lat">South west latitude of the box</param>
/// <param name="gridWidth">Grid witdh</param>
/// <param name="gridHeight">Grid height</param>
/// <param name="grid">Clustering grid</param>
/// <param name="clusteredPoints">Clustered points</param>
/// <returns>Clustered point list</returns>
private void CreateGridAndPutPoints(List <Point> points, int iconSize, double zoomLevel, double?ne_lng, double?ne_lat, double?sw_lng, double?sw_lat, out int gridWidth, out int gridHeight, out ClusterCentroid[][] grid, out List <Point> clusteredPoints)
{
// In order to get grid x and y coordinates,
Point upperRightPoint = new Point()
{
Geometry = new Geometry()
{
Coordinates = new double[] { ne_lng.Value, ne_lat.Value }
},
};
Point lowerLeftPoint = new Point()
{
Geometry = new Geometry()
{
Coordinates = new double[] { sw_lng.Value, sw_lat.Value }
},
};
double upperRightX, upperRightY;
upperRightPoint.Get2DCoordinates(zoomLevel, out upperRightX, out upperRightY);
double lowerLeftX, lowerLeftY;
lowerLeftPoint.Get2DCoordinates(zoomLevel, out lowerLeftX, out lowerLeftY);
gridWidth = (int)(400 / iconSize);
gridHeight = (int)(300 / iconSize);
grid = new ClusterCentroid[gridHeight][];
for (int i = 0; i < gridHeight; i++)
{
grid[i] = new ClusterCentroid[gridWidth];
}
clusteredPoints = new List <Point>();
foreach (var p in points)
{
int x, y;
FindGridCell(grid, p, zoomLevel, upperRightX, upperRightY, lowerLeftX, lowerLeftY, iconSize, out x, out y);
if (grid[y][x] == null)
{
p.Label = y + "-" + x;
grid[y][x] = new ClusterCentroid(p);
clusteredPoints.Add(grid[y][x]);
}
else
{
grid[y][x].AddPoint(p);
}
}
}
/// <summary>
/// Calculates Euclidean Distance distance between a point and a cluster centroid
/// </summary>
/// <param name="p">Point</param>
/// <param name="c">Centroid</param>
/// <returns>Calculated distance</returns>
private double CalculateEuclideanDistance(ClusterPoint p, ClusterCentroid c)
{
return Math.Sqrt(Math.Pow(p.PixelColor.R - c.PixelColor.R, 2.0) + Math.Pow(p.PixelColor.G - c.PixelColor.G, 2.0) + Math.Pow(p.PixelColor.B - c.PixelColor.B, 2.0));
}
